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The geometries of the lowest-lying isomers of Au n Y 2 ( n =1–4) clusters are determined systematically via the density functional method B3LYP with relativistic effective core potentials (RECP) and LANL2DZ basis set. Several low-lying isomers were determined, and many of them in electronic configurations with a high-spin multiplicity. The gold–yttrium interaction is strong enough to modify the known growth pattern of bare gold clusters. The stability trend of Y-doped Au n clusters is compared to that of pure Au n clusters. The results show that the inclusion of two Y atoms in the clusters improves the cluster stability, and indicate higher stability as the structures grow in size. The present calculations are useful to understand the enhanced catalytic activity and selectivity gained by using yttrium-doped gold catalyst.

The geometries of the lowest-lying isomers of Au n Pt 2 , ( n =1–4), clusters are determined using the density functional method B3LYP with relativistic effective core potentials (RECP) and LANL2DZ basis set. Several low-lying isomers were determined, and many of them in electronic configurations with a high spin multiplicity. The stability trend of Pt-doped Au n clusters are compared to that of pure Au n clusters. Our results show that the gold–platinum interaction is strong enough to improve the cluster stability, and indicate that the larger the Au n cluster is, smaller the distortions by substitution of the two Pt atoms are.

Palladium-doped gold clusters, AunPd2 ( n = 1 – 4 ), were investigated by two Pd-atom substitutions on the Aun clusters using the density functional method Becke3LYP with relativistic effective core potentials (RECP) and LANL2DZ basis set. The possible stable geometrical configurations with their electronic states are determined, and the stability trend of Pd-doped Aun clusters are compared to that of pure Aun clusters. Our results show that the gold–palladium interaction is strong enough to modify the known growth pattern of bare gold clusters, and indicate that the larger the Aun cluster is, smaller the distortions by the two Pd-atom substitutions are. The present calculations are useful to understand the enhanced catalytic activity and selectivity gained by using palladium-doped gold catalyst.

Density functional calculations have been performed for the structural, electronic, and magnetic properties of Au5M (M = Sc-Zn) clusters. Geometry optimizations indicate that the M atoms in low-energy Au5M isomers prefer to occupy the most highly coordinated position. The ground-state clusters except Au5Sc possess a planar structure. The vibrational spectra of the doped clusters are completely different from that of a pure gold cluster. The relative stability and chemical activity are investigated through the averaged binding energy and energy gap for the most stable Au5M clusters. It is found that the impurity atoms (not including the Zn atom) can enhance the thermal stability of the host cluster. The chemical activity of Au5M clusters is higher than that of the Au6 cluster. The calculated energy gaps are in accord with available approximate experimental data. The vertical ionization potential, the electron affinity, and photoelectron spectrum are computed and simulated theoretically for all of the ground-state clusters. The magnetism analyses show that the magnetic moment of these Au5M clusters varies from 0 to 5 μB by substituting a Au atom in a Au6 cluster with various M atoms and is mainly localized on the M atom for M = Ti-Ni.